Apparatus for distilling petroleum-oils



A. D. SMITH.

APPARATUS FOR DISTILLING PETROLEUM OILS.

APPLICATION FILED MAR. 13, 1917" 2 SHEETS-SHEET 1.

I Patented Apr. 12, 1921.

A. D. SIVIITH.

I APPARATUS FOR DISTILLING PETROLEUM OILS.

APPLICATION FILED MAR. I3, I917- 7 1,374,402 Patented 12, 1921.,

2 SHEET 2.

UNITED STATES PATENT OFFICE.

ARTHUR 1). SMITH, ,OIF ARKANSAS CITY, KANSAS.

Specification of Letters Patent.

Patented Apr. 12, 1921.

Application filed March 13, 1917. Serial No. 154,469.

To all whom it may concern:

Be it known that I, ARTHUR D. SMITH, a citizen of the United States, and a resident of Arkansas City, in the county of Cowley and State of Kansas, have invented a new and useful Improvement in Apparatus for Distilling Petroleum-Oils, of which the following is a specification.

My invention relates to an improved form of still particularly adapted to be used where heavy parafiin oil, fuel oil, or gas oil is distilled under a pressure ran ing from about one hundred and twenty- 've (125) pounds to -one hundred and fifty (150) pounds, and at a temperature ranging from a closed system of connecting channels while being rapidly circulated throughout the system, the suspended carbon in the charge is removed by mechanical filtration of portions thereof, and the filtered oil is returned to the system, together with as much fresh oil as is required, for maintainin the operation of the still continuously. ne feature of my invention consists in sloping the main shell portion of the still as well as the tubular portion in order the more readily to effect circulation and prevent any deposit of carbon within the still. A further feature is the mechanical means provided for aiding circulation and preventlng any deposit of carbon. Other features of the 1nvention appear in connection w th the description of the apparatus hereinafter described.

In order that my invention ma be more clearly understood, I will descri e it em- .bodied in a suitable form of apparatus,

which I have found in practice to operate satisfactorily, reference being had to the ma companying drawing, wh1ch illustrates a preferred form of the invention.

What I claim as my invention is set forth in the appended claims.

In the drawings, wherein the same reference characters are used to designate the same parts in the several views,

Figure 1 is a side elevation of the apparatus show1ng it diagrammatically;

1g. 2 is a vertical transversecross-section of the still, on the line 2-2 in Fig. 1, look- 111%111 the direction of thearrows; and

1g. 3 is an enlarged vertical transverse cross-section of the lower portion of the main shell of the still, on the line 33 looking in the direction of the arrows.

Referring now particularly to Fig. 1 of the drawings, the apparatus comprises a furnace 1 of ordinary construction with customary fire door 2, ash pit door 3, ash pit 1,

fire grate 5, up flue passage 6, down fiue passage 7, and final up take 8 to stack 9. Suspended from a gallows frame 10 by U bolts 11 is the main shell 12 of the still, which is of conical section, and is arranged with its axis horizontal so that its bottom slopes down toward the rear end. Beneath the shell 12 are the downwardly and rearwardly inclined connecting tubes 13 which are joined to the ends of the main shell by the headers 14L The large conical end of the still is provided with an inclined vapor outlet line 15, which leads to the condenser.

The bottom of the rear header 14; is pro- I vided with a filter well 16, connecting to filter 17 through flow pipes 18, which are provided with valve 19 for controlling intermittent filtration. The filter is provided with perforated false bottom plates 20 of heat resisting metal for supporting suitable filtering media 21, and have man plates 22 for cleaning them. Filtered oil is taken from the bottom of the filter 17 through suction line 23 controlled by valve 24 to a rotary pump 25. The latter is of ordinary type exceptlng that it is furnished with 011 cooled bearings 26 of special design. Oil is returned to the system through a vertical pipe 27 which discharges into the front end 32 are arranged to rotate, so as to produce positive cyclic circulation of the charge in the still along its bottom from front to rear, part of the charge returning through the tubes 13 and part flowing back in theshell over the brushes. Thebrushes are arranged on parallel shafts 33, which are connected by driving chains 34. One of-the shafts 33 projects through an oil cooled stufiing box 35 and has asprocket wheel ,36 on its outer end which is rotated from any suitable source of power, such as the motor driven line shaft 37. The shaft 33 is cooled by oil which is circulated through a system of duct-s '38 drilled in it from a box 39 on its end. The stufling boxes 35 and 39 are of similar design to that employed in the pump 25', and each has a chamber 40 surrounding the rotating shaft through which cool oil is causedto circulate by a suitable pump 41 and oil circulating pipes 42 and 43. Within the upper part of the main shell 12 of the still is a coiled pipe 44 or series of radiating tubes provided with an inlet pipe 45 and an outlet pipe 46 for circulating oil through the vapor space in the still. The outlet pipe has two branches, controlled by valves 47, one of which branches leads to a cooling coil 48 and the other leads to a heating coil 49. A pump 50 is provided for circulating oil through the radiating pipe or tubes 44*and through either the cooling coil 48 or the heating coil 49. The pump 50 is provided with oil cooled stuffing boxes and is driven from the line shaft 37 like the pump 25. An automatic expansion valve 51 is provided to relieve excess pressure in the coil 44; This valve discharges through a pipe which connects to the suction line 30. A branch of the suction line 30 leads to the suction side of the pump 50 to fill the coil 44 opening the valve 52. 4

The stuffing boxes and bearings for the as needed by pumps 25 and 50 are cooled by oil circulated throu h the pipes 53 and 54 by the pump 41. cooling coil 55 is provided for cooling the circulating oil, and control valves 56 permit the flow of cooling oil to the various stuffing justed. A relief valve 57 and a suction Valve 58 are provided in the outlet and inlet pipes for the pump 41, which communicate with the storage tank 29 through branches of'the suction pipe 30. Two recording thermometers 59 are provided for controlling the operation of the still, one entering the still below the normal liquid level (indicated by the line 67 in Fig. 1), the other entering the still in what is normally gaseous space. The sill is also provided with a recording pressure gage 60 and man necks 61.

The operation of the apparatus described boxes to be properly adabove is as follows: The still is first filled with heavy hydrocarbon oil and isv heated to a temperature of approximately six hundred (600) to seven hundred (.700')degrees Fahrenheit. The air is expelled and the pressure allowed to reach one hundred and twenty-live, (125) to one hundred and fifty (150) pounds. The vapor which passes off through the pipe 15 is condensed in the coiled portion 62 in the Water tank 63 and is released as liquid condensate into a re; c'eiving tank 64. The waste water from the tank 63 flows through the spray 65 and drips over the cooling coils 48 and 55;

Pressure and temperature are regulated by suitable manipulation of the fire in the grate and the release valve 66 on the receiving tank; also by circulating hot or cold oil through the vapor temperature controlling tubes 44 as may be desired. The positive circulating system in the still, consisting of the brushes 32,. is then started and maintained throughout the entire period of oper- L ation. Every four to five hours, or as oocasion may require, the entire charge is drawn through the filters 17 alternating fromone to another by proper manipulation of the control valves, as may be required for cleaning out the filters; and at suitable intervals fresh oil is introducedinto the system through the suction valve 31 for rendering the operation of the apparatus continuous. The volume of oil in the still is determined by the difference in temperature" as denoted by the control thermometers 59 which are immersed in the liquid and gaseous levels, respectively, the gaseous portion of the still charge always being from one hundred (100) to one hundred and fifty (150) degrees lower in temperature than the liquid portion. Cold oil supplied by the cooling pump 41 is constantly forced to the oil cooled bearings of the circulatory system throughout the oper-' ation of the still, and also to the bearings of the vapor temperature control pump if the latter is pumping hot oil, in order to prevent the packing from burning out and stopping the operation of the still.

I have heretofore discovered that the sloping bottom of the still increases the tendency toward circulation and diminishes carbon deposition, and I have further discovered that the conical shape of the main shell allows the vapor to'rise more quickly to a portion of the still which can be kept comparat-ively coolwith aid of the vapor temperature control coils, thereby preventing overheating of the vapor beyond four hundred and fifty (450) degrees Fahrenheit, which efi'ects an increased yield of permanent light hydrocarbons.

It is evident that changes in the shape and arrangement of the parts of the apparatus prising a main shell having a sloping bottomand sloping tubular portions connected to said shell at their ends and exposed to heat, so as to induce a cy'cliccirculation through said tubes and shell, and a well below and communicating with the lower end of said shell, said sloping bottom lessening carbon deposition by promoting continuousunovement of'the heavier parts of the still charge.

2. The combination of a still for treating petroleum oils" comprising a shell portion and a tubular portion provided with sloping surfaces, a temperature control coil in the vapor space of said shell, togetherwith a mechanical circulating device in the bottom of said shell to produce circulation of the still contents, thereby preventing overheating and carbon deposition.

3. In combination, in an apparatus of the character described, a still having a downwardly sloping lower surface, a system of closed ducts. connecting the lower end of said surface with its upper end, said system of ducts being exposed to the actionof heat, and means within said still for circulating its fluid and semi-fluid contents toward the lower end of said surface, and a well be'low and communicating with the lower'end ofsaid shell. I

4. In combination, in an apparatus of the character described, a still having a downwardly sloping lower surface, a system of closed ducts connecting the lower end of said surface with its upper end, said system of ducts sloping oppositely to the slope of said lower surface and being exposedto the action of heat, means located at the lowermost point of said system for drawing off portions of the contents thereof and removing the carbon therefrom, means for returning said portions to the 1 still, and means within said still for circulating its fluid and semi-fluid contents toward the lower end of said surface.

5. The combination with a petroleum still having meansfor continuously mechanically propelling its liquid charge to effect rapid cyclic circulation thereof of a mechanical filtering device and an external circuit leading from the lower portion of the still system through such filtering device and back to the still, whereby suspended carbon may be removed intermittently and the carbon free oil returned to the system.

. 6. The combination of a petroleum distillation still having a sloping bottom arranged for cyclic circulation within it, an external circuit arranged to receive oil from said still and return it" thereto, a filtering device and means operable at will for connecting.

said filtering device in said external circuit, and an external source of supply of oil, whereby suspended carbon may be removed intermittently and the carbon free oil returned to the system together with as much fresh oil as is necessary to make the process continuous.

7 The combination with a petroleum still of a plurality of thermometer devices exposed at different levels therein, one of said devices being exposed in the vapor'space in the upper part of the still and another being exposed at such elevation in said still as to be covered by the normal liquid charge and be uncovered whenever the char e. falls a comparatively small dis-- having a temperature control coil in the I vapor space thereof of a plurality of thermometer devices exposed at different levels therein, one of said devices being exposed in the vapor spacein the upper part of the still and another being exposed at such elevation in said still as to be covered by the normal liquid charge and be uncovered whenever the charge falls abnormally low,

whereby the difference in temperature between the liquid and gaseous media indicates whether or not the charge needs replenishing.

s1 ed at St. Louis Missouri this 7th day of h i'ch, 1917.

ARTHUR B. SMITH. 

